REVIEWED: example: Compute shader Game-of-life

examples/others/resources/shaders/glsl430/gol_transfert.glsl

@@ -0,0 +1,51 @@
+#version 430
+
+// Game of life transfert shader
+
+#define GOL_WIDTH 768
+
+// Game Of Life Update Command
+// NOTE: matches the structure defined on main program
+struct GolUpdateCmd {
+    uint x;         // x coordinate of the gol command
+    uint y;         // y coordinate of the gol command
+    uint w;         // width of the filled zone
+    uint enabled;   // whether to enable or disable zone
+};
+
+// Local compute unit size
+layout (local_size_x = 1, local_size_y = 1, local_size_z = 1) in;
+
+// Output game of life grid buffer
+layout(std430, binding = 1) buffer golBufferLayout
+{
+    uint golBuffer[]; // golBuffer[x, y] = golBuffer[x + GOL_WIDTH * y]
+};
+
+// Command buffer
+layout(std430, binding = 3) readonly restrict buffer golUpdateLayout
+{
+    uint count;
+    GolUpdateCmd commands[];
+};
+
+#define isInside(x, y) (((x) >= 0) && ((y) >= 0) && ((x) < GOL_WIDTH) && ((y) < GOL_WIDTH))
+#define getBufferIndex(x, y) ((x) + GOL_WIDTH * (y))
+
+void main()
+{
+    uint cmdIndex = gl_GlobalInvocationID.x;
+    GolUpdateCmd cmd = commands[cmdIndex];
+
+    for (uint x = cmd.x; x < (cmd.x + cmd.w); x++)
+    {
+        for (uint y = cmd.y; y < (cmd.y + cmd.w); y++)
+        {
+            if (isInside(x, y))
+            {
+                if (cmd.enabled != 0) atomicOr(golBuffer[getBufferIndex(x, y)], 1);
+                else atomicAnd(golBuffer[getBufferIndex(x, y)], 0);
+            }
+        }
+    }
+}